javAPRS
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PNG Image Maps


javAPRS has the ability to display any png file, and use it as a map. To do this, first specify the file, which must be in the maps directory as noted above.

<PARAM name="gifMap" value="atlanta.png">

The map must then be calibrated so that javAPRS can plot items correctly onto the map, by specifying the edges of the map in degrees.

<PARAM name="gifMapLeft" value="80.3245">
<PARAM name="gifMapTop" value="24.2454">
<PARAM name="gifMapRight" value="79.4623">
<PARAM name="gifMapBottom" value="23.8916">

(Positive degrees in the north and west hemispheres, and negative in the south and east.)

If you want the applet to match the dimensions of the PNG, the following "rule" applies: each selection bar is 22 pixels high. Therefore, if you do not use a map list or pickBackgroundColor, make the applet the same size as the PNG. If you do use one of those options, make the applet height = the PNG height + 22.

You must also include the necessary jar files in case the user is using an older browser or JVM. The proper jar files to add are japrspng.jar and japrspng.cab if not a pre-OS X Mac or japrspngmac.jar for a pre-OS X Mac.

<APPLET ... archive="japrs.jar,japrspng.jar">
<PARAM name="cabinets" value="japrs.cab,japrspng.cab">


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